• Research in Plant Disease
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• v.9 no.4
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• pp.221-223
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• 2003

In May 2002, a destructive stem rot of Obedient plant (Physostegia virginiana) occurred sporadically in an exhibition farm of Hamyang-gun, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptoms of the disease were stem rot, crown rot, wilt or blight. Upper parts of the infected stems were mostly blighted. White mycelial mats were spread over lesions and the sclerotia were formed on the stems near soil line. The sclerotia was globoid or irregular in shape, 1${\sim}$3 mm in size, and brown in color. The optimum temperature for fungal growth was about $30^{\circ}C$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA, and hyphal diameter was 3.6${\sim}$9.4 ${\mu}m$. On the basis of mycological characteristics and test of pathogenecity to host plants, the fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of Physostegia virginiana caused by Sclerotium rolfsii in Korea.

• Research in Plant Disease
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• v.9 no.1
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• pp.25-27
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• 2003

In 2002, a stem rot disease was found on Pansy (Viola tricolor) in several road-side flower beds in Jinju City, Gyeongnam province, Korea. The typical symptoms of the disease were stem rot, crown rot, wilt or blight. Upper parts of the infected stems were mostly blighted. White mycelial mats were spread over lesions and the sclerotia were farmed on the stems near soil line. The sclerotia was globoid or irregular in shape, 1.3~4.2 mm in size, and brown in color, The optimum temperature for fungal growth was about 3$0^{\circ}C$. The typical clamp connections were found in the hyphae of the fungus grown on PDA, and hyphal diameter was 3.9~10.4 ${\mu}{\textrm}{m}$. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of Viola tricolor caused by Sclerotium rolfsii in Korea.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.559-565
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• 2013

This study evaluated the ability of white and brown rot fungi to decompose fire retardant-treated wood by measuring mass loss. Anti efficacy of FRT against sapstain and mold fungi was evaluated. Wood was treated with liquid sodium silicate and boric acid, ammonium borate, di-ammonium phosphate. Retardant treated wood was then subjected to fungal decay resistance tests performed according to KS standard method using a brown-rot fungus, Fomitopsis palustris and white rot fungus Trametes versicolor. Aspergillus niger, Penicillium funiculosum, Rhizopus nigricans, Aureobasidium pullulans, Tricoderma virede fungi were used anti-sapstain and mold test. Boron and phosphorus chemicals used in this study increased the resistance of fire retardant treated wood against both fungal attack. Anti mold and sapstain efficacy of the fire retardant treated wood was excellent but there were difference depend on mold. After the liquid sodium silicate treatment, the second chemical treatment process could lead chemical fixation into wood, which effects decay resistance.

• Research in Plant Disease
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• v.11 no.1
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• pp.85-87
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• 2005

In July 2003, a destructive stem rot occurred sporadically in an exhibition farm on Aster glehni of Hamyanggun, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptoms of the disease were water-soaking, stem rot, wilt or blight. The infected plants were mostly died. White mycelial mats were spread over lesions and sclerotia were formed on stems and near soil line. The sclerotia were globoid or irregular in shape, 1~3 mm in size, and white to brown in color. The optimum temperature for fungal growth was about 30oC. Clamp connections were observed in the hyphae of the fungus grown on potato dextrose agar, and hyphal diameter was 3~8 ${\mu}m$. On the basis of mycological characteristics and test of pathogenicity to host plants, the fungus was identified as Sclerotium rolfsii. This is the first report on the stem rot of Aster glehni caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.18 no.1
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• pp.54-56
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• 2012

Sclerotium rot of sponge gourd occurred at the experimental field of Gyeongsangnam-do Agricultural Research and Extension Services in August 2010. The infected fruits showed water-soaked and rot symptoms. White mycelial mats spread over lesions, and then sclerotia were formed on fruit and near soil line. The sclerotia were globoid in shape, 1-3 mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$ and the hyphal width was 4-8 ${\mu}m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics, ITS rDNA sequence analysis, and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot on sponge gourd caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.18 no.1
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• pp.57-61
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• 2012

In March 2010, grafted cucumber cultivated in the greenhouse showed a severe rot on crown resulting yellowing and wilting of the leaves. The symptoms of naturally infected plants showed dark brown, watersoaked lesions at the base of the stem. The fungus produced mass of white mycelium and yellow to orange spores in necrotic lesions on dead and dying plants. Fungus was isolated from rotted tissues of the crown and root. On the basis of morphological characteristics, ITS sequence and pathogenicity tests, the isolate was identified as Fusarium solani f. sp. cucurbitae. This is the first report of the crown and foot rot of grafted cucumber caused by F. solani f. sp. cucurbitae in Korea.

• The Korean Journal of Mycology
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• v.51 no.1
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• pp.51-56
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• 2023

Dendropanax trifidus belonging to the family Araliaceae, is a warm-temperate evergreen tree distributed in Jeju Island, Bogil Island, Geomun Island, Geoje Island, Wando, and Haenam in Korea. In June 2021, a root rot disease in which branches of Dendropanax trifidus seedlings turned brown and shrunk was discovered at the seedling cultivation facility in Naju-si, Republic of Korea. To identify the root rot fungus, three strains were isolated from the diseased tissues of seedlings and their mycological characteristics were investigated on potato dextrose agar. In addition, a molecular phylogenetic analysis was performed using sequences of the internal transcribed spacer (ITS) region and translation elongation factor 1-α (EF1-α) gene. The fungus was identified as Fusarium oxysporum. For pathogenicity test, the roots of seedlings were immersed in the conidia suspension of the strains and planted. After 20 days inoculation, root rot and browning symptoms were confirmed in the inoculated plants. This is the first report of F. oxysporum on D. trifidus in Korea.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.90-92
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• 2008

In 2007, a bulb rot of Allium victorialis var. platyphyllum Makino caused by Sclerotium rolfsii occurred sporadically in a herb farm at Gyeongsangnam-do, Korea. The symptom initiated with water-soaking lesion and progressed into bulb rot and wilt of a whole plant. Severely infected plants were blighted and killed eventually. White mycelial mats appeared on the lesion at early stage and a number of sclerotia were formed on the bulb. The sclerotia were spherical, $1{\sim}3 mm$ and white to brown. The optimum temperature for the growth and sclerotia formation was $30^{\circ}C$ on PDA. The hyphal width was measured $4-9{\mu}m$. The typical clamp connections were observed on PDA. Based on the symptom, mycological characteristics and pathogenicity to the host plant, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the bulb rot of A. victorialis var. platyphyllum caused by S. rolfsii in Korea.

• Research in Plant Disease
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• v.17 no.3
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• pp.396-398
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• 2011

Soft rot disease on Raspberry (Rubus crataegifolius Bunge) was observed in sale boxes at Jinju City Wholesale Market of Agricultural Products in June 2010. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The colonies on the infected fruits were white to light brown, formed numerous sporangiospores. Optimum temperature for the mycelial growth of the causal fungus on PDA was $30^{\circ}C$ and growth was still apparent at $37^{\circ}C$. Sporangia were globose, white at early and gradually to black, and 40-210 ${\mu}m$ in diameter. Sporangiophores were white to mid brown as maturation and 8-20 ${\mu}m$ in diameter. Columella were globose to sub-globose, and the size of the diameter was 85-120 ${\mu}m$ in diameter. Sporangiospores were sub-globose, rhomboidal and irregular, streaked and 5-10 ${\mu}m$ in length. On the basis of symptom, mycological characteristics, ITS rDNA sequence analysis, and pathogenicity of the fungus, the causal fungus was clearly identified as Rhizopus oryzae Went & Prinsen Geerligs. This is the first report of soft rot by R. oryzae on R. crataegifolius in Korea.

• Research in Plant Disease
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• v.19 no.4
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• pp.300-307
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• 2013

This study was conducted to determine the occurrence of leaf rot and leaf ring spot, caused by Rhizoctonia solani in Chinese cabbage under seedling nursery and cultivation greenhouses. Symptoms of leaf rot and leaf ring spot were found in three Chinese cabbage cultivars, Brassica campestris subsp. pekinensis, 'Ryeokgwang', 'Daetong', and 'CR mat'. In Hwacheon, the disease incidence was 73.8% in the seedling stage of the Chinese cabbage. In Icheon, the symptoms were observed on the upper leaves of the Chinese cabbage cultivar, 'Norangmini' with 20.5% of disease incidence. The symptoms appeared as primary lesions consisting of small, circular necrotic ring spots with gray color, 1.4-3.0 mm in diameter, accompanied by secondary rot lesions with large irregular borders of leaves. The color of mycelial mat of 20 isolates was dark brown and light brown. The average hyphal diameter of all the isolates was within 5.01-11.12 ${\mu}m$. Among the 20 strains isolated from Chinese cabbage, 16 isolates and four isolates anastomosed with the AG-1 (IB) and AG-1 (IC), respectively. Twenty isolates tested were only virulent on foliage parts of Chinese cabbage leaves but were avirulent on stem parts of the plants. Based on the mycological characteristics and pathogenicity test on host plants, the fungus was identified as Rhizoctonia solani.